Well, I'm far from being an expert about cron. But from what I've seen,
it seems that the cron jobs that are defined by default in Fedora are
"system" jobs. They belong to root and could not be modified without
having the root password.
So my question is: do we want to be able to handle "system" jobs too ?
Or do we limit our field to "userland" jobs ?
If we decide to handle system jobs, we'll obviously have to mess with
the run-parts stuff. But if we don't, I don't see any reason why we
should use run-parts.